The present invention relates to dust filters.
More particularly the present invention concerns a funnel for collecting dust separated by a filter.
It is known in the prior art to provide a gas-filtering system with a collecting funnel for leading dust separated by a filter to an arrangement for transporting the thusly collected dust away from the filter.
The separated dust tends to create a cake in such a funnel, which can result in plugging the same. In this case the interior of the funnel eventually may become extremely obstructed so that no dust will leave this funnel through the corresponding outlet thereof. In order to decrease the dust accumulation tendency it is known to provide the inside wall of the funnel with a low-friction covering to thereby facilitate sliding of the dust through the funnel. Obviously this low friction covering is quite expensive. However, crystalline dust considerably abrades this covering, making the latter practically inefficient.
It has been recognized, that the dust, especially fine-grain dust has a tendency to accumulation, especially along welded joints of the funnel. Such dust deposits can eventually result in plugging the outlet of the funnel. Therefore, the welded joints which connect the walls of the funnel must be very carefully polished. In the case of a rectangular funnel, it is especially likely that the dust will deposit along the connecting angles of the funnel walls. In order to prevent dust deposit process along these angles it is preferable to provide the funnel with the most possible inclination. Such a feature will obviously lead to increasing the overall height of the funnel, which involves additional expenses. Moreover, in order to further prevent dust accumulation, the angle portions of the funnel have to be covered with sheets. However, the additional sheets involve additional welded joints and consequently additional polishing operations of these welded joints.